M31 - Andromeda

Here is an image made with an SLR lens. (I have been trying lenses lately for wide field). It is a familiar object - M31. I have heard some recommend stopping down an SLR lens a step or two for better results. I took some luminance exposures at f/3.5 and some at f/4.5. The f/4.5 images came out clearly better with less star bloat. Of course exposure time was increased accordingly to achieve the same signal strength. I am only showing the f/4.5 data in this image.

I have attached a mid size image - a full size image and exposure / processing details are at:

http://jthommes.com/Astro/m31.htm

Lens was a Vivitar 180mm telephoto, camera was an Artemis285.

Total exposure was a relatively short 63 minutes.

Attached Image:

A tremendous FOV. I am seeing some green stars

Brian and Warren

Ha! What an embarrasing situation! Yes, I too thought the colors were somewhat funky. Just wrote it off and tried to rebalance to what I have seen of M31 as best I could.

So then I receive Warren's thoughtful comment, and go back to take a look. Well apparently I used the same color channel for red and green! (Looks like red was used for both red and green).

So I will go back and reprocess to see what happens (its got to be better). Sorry to bother you all with my error. Warren thanks again for the comments that made me go back to look.

(I gotta stop processing late at night.)

Great shot Jim. I have been playing with telephoto lenses also, but I have to use film for now. Don't have a ccd or dslr camera yet. I am looking at the Orion CCD camera but want to see some reviews first.
This shot was a couple weeks ago in Chiefland, FL. One hour on Fuji 400 color neg. I used a 350mm f/5.5 t-mount lens, stopped down to 6.3.
I scanned the print and tweaked a little in PS Elements.

Walt

Attached Image:

Nice photo Jim. I went to your link for the processing details and got to say, I need to take some classes on processing digital photos! Here is one I took with a Canon 20Da. The only processing I can do and KNOW what I'm doing is the levels adjustment in photoshop. I just moved the lefthand slider over to the dark pixel curve to get rid of the sky fog. This was a 10 minute exposure throught a Stellarvue AT1010. Notice all the blue around the bright stars. I sold it and have an Orion 80ED on order.

Attached Image: